It has been attempted to recycle used sanitary products such as disposable paper diapers. For recycling of used sanitary products, it is common to disintegrate the used sanitary products in water, separating them into the constituent components of the sanitary products, which are then recovered. However, the polymer absorbents that are included in sanitary products absorb moisture and increase in mass, while also gelling and losing their flow property, causing the throughput capacity of the treatment apparatus to be reduced.
Patent Document 1 therefore discloses using lime for dehydration of polymer absorbents in used paper diapers that have absorbed moisture (claim 2). This reduces the weight of the polymer absorbent, while also restoring the gel state to the original state and recovering its flow property, so that reduction in the throughput capacity of the treatment apparatus can be avoided (paragraph [0020]).